Question: Simplify the expression. $(-3y)(4y^{3}-y^{2}+7y)$
Answer: First use the distributive property. $ - 3 y (4 y^3) - 3 y (- y^2) - 3 y (7 y) $ Simplify. $-12y^{4}+3y^{3}-21y^{2}$